different methods of teaching science

Outbreak alert: six students at the Chicago State Polytechnic University in Illinois have been hospitalized with severe vomiting, diarrhoea and stomach pain, as well as wheezing and difficulty in breathing. Some are in a critical condition. And the university's health centre is fielding dozens of calls from students with similar symptoms.

This was the scenario that 17 third- and fourth-year undergraduates dealt with as part of an innovative virology course led by biologist Tammy Tobin at Susquehanna University in Selinsgrove, Pennsylvania. The students took on the role of federal public-health officials, and were tasked with identifying the pathogen, tracking how it spreads and figuring out how to contain and treat it — all by the end of the semester.

Although the Chicago school and the cases were fictitious, says Tobin, “we tried to make it as real as possible”. If students decided to run a blood test or genetic assay, Tobin would give them results consistent with enterovirus D68, a real respiratory virus. (To keep the students from just getting the answer from the Internet, she portrayed the virus as an emergent strain with previously unreported symptoms.) If they decided to send a team to Chicago, Tobin would make them look at real flight schedules and confirm that there were enough seats.

In the end, the students pinpointed the virus, but they also made mistakes: six people died, for example, in part because the students did not pay enough attention to treatment. However, says Tobin, “that doesn't affect their grade so long as they present what they did, how it worked or didn't work, and how they'd do it differently”. What matters is that the students got totally wrapped up in the problem, remembered what they learned and got a handle on a range of disciplines. “We looked at the intersection of politics, sociology, biology, even some economics, ” she says.

Tobin's approach is just one of a diverse range of methods that have been sweeping through the world's undergraduate science classes. Some are complex, immersive exercises similar to Tobin's. But there are also team-based exercises on smaller problems, as well as simple, carefully tailored questions that students in a crowded lecture hall might respond to through hand-held 'clicker' devices. What the methods share is an outcome confirmed in hundreds of empirical studies: students gain a much deeper understanding of science when they actively grapple with questions than when they passively listen to answers.

“We find up to 20% better grades over usual methods, ” says Tom Duff, a computer scientist who developed a team-based learning approach at the University of the West of Scotland in Paisley, UK. Other active-learning proponents have found similar gains. Last year, a group led by biologist Scott Freeman at the University of Washington in Seattle published an analysis of 225 studies of active learning in science, technology, engineering and mathematics (STEM) and found that active learning cut course failure rates by around one-third.

“At this point it is unethical to teach any other way, ” declares Clarissa Dirks, a microbiologist at the Evergreen State College in Olympia, Washington, and co-chair of the US National Academies Scientific Teaching Alliance, an initiative to reform undergraduate STEM education.